/***************************************************************************
 * Linux PPP over X - Generic PPP transport layer sockets
 * Linux PPP over Ethernet (PPPoE) Socket Implementation (RFC 2516) 
 *
 * This file supplies definitions required by the PPP over Ethernet driver
 * (pppox.c).  All version information wrt this file is located in pppox.c
 *
 * License:
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */

#ifndef __LINUX_IF_PPPOX_H
#define __LINUX_IF_PPPOX_H

#include <linux/types.h>
#include <asm/byteorder.h>

#ifdef  __KERNEL__
#include <linux/if_ether.h>
#include <linux/if.h>
#include <linux/netdevice.h>
#include <linux/ppp_channel.h>
#endif /* __KERNEL__ */
#include <linux/if_pppol2tp.h>
#include <linux/if_pppolac.h>
#include <linux/if_pppopns.h>

/* For user-space programs to pick up these definitions
 * which they wouldn't get otherwise without defining __KERNEL__
 */
#ifndef AF_PPPOX
#define AF_PPPOX	24
#define PF_PPPOX	AF_PPPOX
#endif /* !(AF_PPPOX) */

/************************************************************************ 
 * PPPoE addressing definition 
 */
typedef __be16 sid_t;
struct pppoe_addr {
	sid_t sid;		/* Session identifier */
	unsigned char remote[ETH_ALEN];	/* Remote address */
	char dev[IFNAMSIZ];	/* Local device to use */
};

/************************************************************************ 
 * Protocols supported by AF_PPPOX 
 */
#define PX_PROTO_OE    0	/* Currently just PPPoE */
#define PX_PROTO_OL2TP 1	/* Now L2TP also */
#define PX_PROTO_OLAC  2
#define PX_PROTO_OPNS  3
#define PX_MAX_PROTO   4

struct sockaddr_pppox {
	sa_family_t sa_family;	/* address family, AF_PPPOX */
	unsigned int sa_protocol;	/* protocol identifier */
	union {
		struct pppoe_addr pppoe;
	} sa_addr;
} __attribute__ ((packed));

/* The use of the above union isn't viable because the size of this
 * struct must stay fixed over time -- applications use sizeof(struct
 * sockaddr_pppox) to fill it. We use a protocol specific sockaddr
 * type instead.
 */
struct sockaddr_pppol2tp {
	sa_family_t sa_family;	/* address family, AF_PPPOX */
	unsigned int sa_protocol;	/* protocol identifier */
	struct pppol2tp_addr pppol2tp;
} __attribute__ ((packed));

/*********************************************************************
 *
 * ioctl interface for defining forwarding of connections
 *
 ********************************************************************/

#define PPPOEIOCSFWD	_IOW(0xB1 ,0, size_t)
#define PPPOEIOCDFWD	_IO(0xB1 ,1)
/*#define PPPOEIOCGFWD	_IOWR(0xB1,2, size_t)*/

/* Codes to identify message types */
#define PADI_CODE	0x09
#define PADO_CODE	0x07
#define PADR_CODE	0x19
#define PADS_CODE	0x65
#define PADT_CODE	0xa7
struct pppoe_tag {
	__be16 tag_type;
	__be16 tag_len;
	char tag_data[0];
} __attribute((packed));

/* Tag identifiers */
#define PTT_EOL		__constant_htons(0x0000)
#define PTT_SRV_NAME	__constant_htons(0x0101)
#define PTT_AC_NAME	__constant_htons(0x0102)
#define PTT_HOST_UNIQ	__constant_htons(0x0103)
#define PTT_AC_COOKIE	__constant_htons(0x0104)
#define PTT_VENDOR 	__constant_htons(0x0105)
#define PTT_RELAY_SID	__constant_htons(0x0110)
#define PTT_SRV_ERR     __constant_htons(0x0201)
#define PTT_SYS_ERR  	__constant_htons(0x0202)
#define PTT_GEN_ERR  	__constant_htons(0x0203)

struct pppoe_hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__u8 ver:4;
	__u8 type:4;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__u8 type:4;
	__u8 ver:4;
#else
#error	"Please fix <asm/byteorder.h>"
#endif
	__u8 code;
	__be16 sid;
	__be16 length;
	struct pppoe_tag tag[0];
} __attribute__ ((packed));

/* Length of entire PPPoE + PPP header */
#define PPPOE_SES_HLEN	8

#ifdef __KERNEL__
#include <linux/skbuff.h>

static inline struct pppoe_hdr *pppoe_hdr(const struct sk_buff *skb)
{
	return (struct pppoe_hdr *)skb_network_header(skb);
}

struct pppoe_opt {
	struct net_device *dev;	/* device associated with socket */
	int ifindex;		/* ifindex of device associated with socket */
	struct pppoe_addr pa;	/* what this socket is bound to */
	struct sockaddr_pppox relay;	/* what socket data will be
					   relayed to (PPPoE relaying) */
};

struct pppolac_opt {
	__u32 local;
	__u32 remote;
	__u16 sequence;
	__u8 sequencing;
};

struct pppopns_opt {
	__u16 local;
	__u16 remote;
	__u32 sequence;
};

#include <net/sock.h>

struct pppox_sock {
	/* struct sock must be the first member of pppox_sock */
	struct sock sk;
	struct ppp_channel chan;
	struct pppox_sock *next;	/* for hash table */
	union {
		struct pppoe_opt pppoe;
		struct pppolac_opt lac;
		struct pppopns_opt pns;
	} proto;
	__be16 num;
};
#define pppoe_dev	proto.pppoe.dev
#define pppoe_ifindex	proto.pppoe.ifindex
#define pppoe_pa	proto.pppoe.pa
#define pppoe_relay	proto.pppoe.relay

static inline struct pppox_sock *pppox_sk(struct sock *sk)
{
	return (struct pppox_sock *)sk;
}

static inline struct sock *sk_pppox(struct pppox_sock *po)
{
	return (struct sock *)po;
}

struct module;

struct pppox_proto {
	int (*create) (struct net * net, struct socket * sock);
	int (*ioctl) (struct socket * sock, unsigned int cmd,
		      unsigned long arg);
	struct module *owner;
};

extern int register_pppox_proto(int proto_num, struct pppox_proto *pp);
extern void unregister_pppox_proto(int proto_num);
extern void pppox_unbind_sock(struct sock *sk);	/* delete ppp-channel binding */
extern int pppox_ioctl(struct socket *sock, unsigned int cmd,
		       unsigned long arg);

/* PPPoX socket states */
enum {
	PPPOX_NONE = 0,		/* initial state */
	PPPOX_CONNECTED = 1,	/* connection established ==TCP_ESTABLISHED */
	PPPOX_BOUND = 2,	/* bound to ppp device */
	PPPOX_RELAY = 4,	/* forwarding is enabled */
	PPPOX_ZOMBIE = 8,	/* dead, but still bound to ppp device */
	PPPOX_DEAD = 16		/* dead, useless, please clean me up! */
};

#endif /* __KERNEL__ */

#endif /* !(__LINUX_IF_PPPOX_H) */
